Last summer the Minnesota Department of Transportation and the State Patrol joined forces to crack down on carpool lane cheats, and Drive reader Kathrine has noticed.

Since new MnPass lanes opened on I-35E in the northeast metro, she frequently sees troopers stopping motorists who illegally use the special lanes that are reserved for buses, motorcycles and carpools with two or more occupants, or solo drivers who pay a fee to use them.

"It's quite astounding," she said. Infuriating, too, as there is nothing like a squad car with flashing lights stopped on the shoulder of a MnPass lane to bring traffic to a slow roll and create a big backup.

"I would love to see traffic move smoothly instead of seeing state troopers being an impediment as they are now," the White Bear Lake reader said. "I've seen troopers move over four lanes of traffic [to make a stop] and that brings traffic to an immediate halt."

She asked why MnDOT does not install cameras to nab scofflaws.

The Drive posed that question to MnPass spokeswoman Bobbie Dahlke, who offered a couple explanations.

First, she said, car poolers would have to register their vehicles and get a MnPass tag because cameras would flag them if they did not detect one on the windshield, even though car poolers are able to use the lanes at no charge. Second, cameras are not a substitute for human eyes, so using them would require legislative approval. Cameras are not always able to give a full crisp view of how many people are in a vehicle. And "we'd have to prove who was driving, and there is a host of other issues," MnDOT freeway operations engineer Garrett Schreiner added.

Cameras might not be far off, however. MnDOT is exploring using cameras to help troopers nab drivers skirting the law. Cameras could help troopers identify vehicles in a High Occupancy Toll (HOT) lane that had only one person in the vehicle or did not have a tag. "We would only use cameras as an assistant, not for full enforcement," Schreiner said.

1,000 citations, 800 warnings

MnDOT is also looking at ways for troopers to use portable readers to determine if a HOT lane driver is a subscriber, like those used by police to scan license plates. In the past two weeks, MnDOT began offering license plate frames with embedded tags. That would be another tool troopers could use to catch cheats.

"Enforcement is a challenge, and we are trying to figure out ways to mitigate that," Dahlke said. "We have enforcement out there pulling people over and we still get complaints. We can't make everybody happy."

Even without technology, troopers have been busy. This year, they have issued nearly 1,000 citations and 800 warnings to drivers illegally using HOT lanes on I-35E, I-35W and I-394. Troopers who spot violators try to pull them over in areas where there are wide shoulders so as not to gum up traffic and keep drivers and troopers out of danger, said Lt. Tiffani Nielson of the State Patrol.

By 2028, MnDOT suggests that metro area highways and freeways may be congested close to 30 percent of the time from 6-10 a.m. and 3-7 p.m. on weekdays, the hours that MnPass lanes are in effect. With gridlock growing, it's no wonder a study in 2014 found 8 percent of MnPass lane users were lawbreakers. MnDOT is conducting another study this summer to get a better idea on how rampant the problem is.

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